Kerx is most often found in Ilelish and the rimward areas of human space, and in the trailing areas of Aslan space, although it is not unknown elsewhere. It appears to be related to several Terran games, including draughts, but there is enough divergence to make the actual origin questionable.
The game is played by two players on a hexagonal board of 37 spaces (four spaces along each edge). Each player has 18 pieces of uniform appearance, which can be easily identified from the opponent's pieces (color, shape, marking, etc.). These pieces are initially placed on the board so that the three rows of spaces nearest the player are filled, and the remaining three pieces are placed on the three spaces to the right of the center space of the fourth (middle) row. The players decide who plays first using any method that they can both agree upon.
Play alternates with each player either moving a piece to an adjacent empty space in any of the six available directions, or jumping over a single opposing piece to an empty space beyond, in any of the six available directions. If making a jump places the jumping piece in position to make further jumps (in any direction other than the one from which the jumping piece came), such continued jumps may be made. After all jumps are completed, the jumped pieces are removed from the board.
Jumps are compulsory; if multiple possible sequences of jumps are available to a player, the longest is compulsory. Failure to take a compulsory jump results in the opponent removing the piece that would have made the compulsory jump, then proceeding with his move as normal.
The game is won when all of the opponent's pieces are captured; a game that reaches a state where both players have only three pieces each is considered a draw.
Variations of Kerx using larger boards (and correspondingly more pieces) are common.